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Beta taxonomic and functional diversity of rotifera in four large neotropical floodplains, Brazil.
No full textThe taxonomic and functional beta diversity of rotifers in floodplains can help understand responses to environmental changes as well as ecosystem dynamics. The taxonomic and functional beta diversity of rotifers was analyzed in four neotropical floodplains (Amazonas, Araguaia, Pantanal, Paraná River), in order to verify whether there are differences in the composition and structure of the rotifer community in the different plains and within each plain between the different periods. Differences in taxonomic and functional beta diversity were tested using multivariate statistics. 128 species of rotifers were identified, 84 in the Paraná River, Amazonas (78), Araguaia (77) and Pantanal (75). Functionally equal species were grouped together. The plains of the Paraná and Amazon rivers were those that showed a significant difference in taxonomic and functional beta diversity during the rainy season. During the dry period, the plains that showed differences were Araguaia and Amazonas and the Paraná and Araguaia rivers. Functional beta diversity did not show a significant difference during the dry period. Changes in taxonomic beta diversity can result in long-term loss of ecosystem function, potentially altering its functioning. Therefore, the study of taxonomic beta diversity must be followed by functional beta diversity to better understand the dynamics and functioning of the ecosystem, as well as its preservation.A diversidade beta taxonômica e funcional de rotíferos em planícies de inundação pode auxiliar na compreensão das respostas frente às mudanças ambientais bem como a dinâmica do ecossistema. Analisou-se a diversidade beta taxonômica e funcional de rotíferos em quatro planícies de inundações neotropicais (Amazonas, Araguaia, Pantanal, rio Paraná), a fim de verificar se existem diferenças na composição e estrutura da comunidade de rotíferos nas diferentes planícies e dentro de cada planície entre os diferentes períodos. As diferenças na diversidade beta taxonômica e funcional foram testadas utilizando estatistica multivariada. Foram identificadas 128 espécies de rotíferos, 84 no rio Paraná, Amazonas (78), Araguaia (77) e Pantanal (75). Espécies funcionalmente iguais foram agrupadas. As planícies dos rio Paraná e Amazonas foram as que apresentaram diferença signicativa na diversidade beta taxonômica e funcional no período chuvoso. No período de seca as planícies que apresentaram diferença foram Araguaia e Amazonas e rio Paraná e Araguaia. A diversidade beta funcional não apresentou diferença significativa no período de seca. Mudanças na diversidade beta taxonômica podem resultar em perda de funções no ecossistema a longo prazo, podendo alterar o seu funcionamento. Portanto, o estudo da diversidade beta taxonômica deve ser seguida pela de diversidade beta funcional para melhor compreensão da dinâmica e funcionamento do ecossistema, bem como para a sua preservação.Master
Особенности пространственного распределения гидрохимических показателей в Куршском заливе Балтийского моря в 2018–2022 годах
No full textCuronian Bay of the Baltic Sea is a lagoon that is considered to be a water body of the highest fisheries importance. Its current geoenvironmental status is characterized by a number of problems: influx of biogenic substances from a large catchment area, algal bloom, etc. As part of the monitoring surveys of the habitat of aquatic living resources that were conducted in Russian waters of Curonian Lagoon in 2018–2022, the spatial distribution of hydrochemical parameters was investigated in 6 areas established on the basis of their morphometric and hydrological features: Teply (Warm) Bay, western, central, eastern, and southern areas, and the Neman River discharge zone. Hydrochemical conditions in Teply Bay were characterized by a considerable deviation of dissolved oxygen concentrations from the rest of Russian waters of Curonian Lagoon, as well as by the higher values of BOD5 and ammonia nitrogen, and lower values of pH and nitrate nitrogen. In the western area, the lowest content of dissolved oxygen, BOD5, ammonia, and nitrate nitrogen was recorded. In the southern area, there was a reduced content of ammonia nitrogen and nitrate nitrogen. In the central area, the values of hydrochemical parameters were close to the average ones for Russian waters. The eastern and Neman River discharge areas, exposed to significant influence of the Neman River runoff, were characterized by a high concentration of nitrate nitrogen during seasonal flood, as well as by increased values of ammonia nitrogen and BOD5 during algal bloom in summer.Куршский залив Балтийского моря представляет собой лагуну и относится к водоемам рыбохозяйственного значения высшей категории. Его современное состояние характеризуется рядом проблем: поступлением биогенных элементов с большого водосбора, «цветением» вод. В рамках мониторинга среды обитания водных биологических ресурсов, проводимого на российской акватории Куршского залива в 2018–2022 гг., изучено пространственное распределение гидрохимических показателей в 6 районах, выделенных с учетом морфометрических и гидрологических особенностей: заливе Теплом, западном, центральном, восточном, южном и неманском районах. Гидрохимические условия в зал. Теплом характеризовались значительным отклонением концентраций растворенного кислорода от остальной российской части, более высокими значениями БПК5 и аммонийного азота, пониженными величинами рН и азота нитратов. В западном районе отмечались низкие величины растворенного кислорода, БПК5, аммонийного и нитратного азота. В южном районе наблюдали сниженное содержание аммонийного азота и азота нитратов. В центральном районе гидрохимические показатели были близки к средним по российской акватории. Восточный и неманский районы, подверженные значительному влиянию стока р. Неман, характеризуются высокой концентрацией азота нитратов в период половодья; также отмечаются повышенные величины аммонийного азота и БПК5 летом при «цветении» вод.PublishedReferee
Evaluación del grado de contaminación metálica en el área de alimentación de tortugas verdes Lanzanillo-Pajonal- Fragoso, Cuba
No full textThe present work evaluates the contamination level by metallic elements in the marine sediments of Lanzanillo-Pajonal-Fragoso Wildlife Refuge, Villa Clara province, Cuba. Eight sampling stations were selected and the levels of Cr were quantified by X-Ray Fluorescence and Zn, Cu, Cd, Fe, Pb, Ni, Mn and Co by Flame Atomic Absorption Spectrophotometry. The chemical pre-treatment of the samples was carried out following the modified ISO 11466 standard method and some validation parameters of the analytical technique were evaluated, showed the accuracy and feasibility of the method. To evaluate the study area contamination the International Sediment Quality Guide of the National Oceanic and Atmospheric Administration and four environmental contamination indexes were used: two enrichment indexes (the enrichment factor and the geoaccumulation index), an ecological risk index (the average ratio of moderate risk effects), and a contamination index (the modified degree of contamination). The results showed that the elements representing the greatest risk are Ni and Cr, since they exceed the concentration that causes Moderate Biological Effects. According to the evaluated indexes, it can be concluded that there is a presence of anthropogenic contamination in the protected area that may be affecting the turtle’s health due to the stress that they cause in them. The site of highest risk was Jácate and the element that more contribute to the metallic contamination is Cr, although significant values were obtained for Ni, Co and Fe.En el presente trabajo se evalúa la contaminación por elementos metálicos en los sedimentos marinos del Refugio de fauna Lanzanillo-Pajonal-Fragoso, provincia Villa Clara, Cuba. Se seleccionaron ocho estaciones de muestreo y se cuantificaron en las mismas los niveles de Cr mediante Fluorescencia de Rayos X y de Zn, Cu, Cd, Fe, Pb, Ni, Mn y Co por Espectrofotometría de Absorción Atómica con llama. El pre-tratamiento químico de las muestras se realizó empleando la norma modificada ISO 11466 y se evaluaron parámetros de validación de la técnica analítica, los cuales mostraron la exactitud y factibilidad del método empleado. Para evaluar la contaminación de la zona de estudio se empleó la Guía Internacional de Calidad de Sedimentos de la Administración Nacional del Océano y la Atmósfera y cuatro índices de contaminación: dos índices de enriquecimiento (el factor de enriquecimiento y el índice de geoacumulación), un índice de riesgo ecológico (el cociente medio de los efectos de riesgo moderado), y un índice de contaminación (el grado modificado de contaminación). Los resultados obtenidos mostraron que los elementos de mayor riesgo son el Ni y el Cr, pues superan la concentración que provoca Efectos Biológicos Moderados. Los índices evaluados permiten concluir que hay presencia de contaminación antropogénica en el área protegida que puede estar afectando la salud de las tortugas debido al estrés que provocan en estas. El sitio de mayor riesgo fue Jácate y el elemento que aporta la mayor con- taminación es el Cr, aunque el Ni, Co y el Fe mostraron valores significativos.PublishedReferee
Proceedings of the 2022 Annual Meeting of the Scientific Committee on Oceanic Research 48th SCOR Annual Meeting, Volume 58, 2022
No full textThis proceeding summarizes the discussions during the 48th SCOR Annual Meeting held in hybrid format from Busan, Korea, between the 4-6 of October of 2022. This proceeding also provides the links for all the background information for the meeting, including the proposals for new working groups, the reports from current SCOR working groups, projects, capacity development activities, and the reports of affiliated and partner organizations all of which were traditionally included in the SCOR Annual meeting background book until 2019. All of these can also be accessed online through the SCOR website at: https://scor-int.org/events/scor-2022-annual-meeting/.PublishedNon Referee
Морфологические характеристики и особенности биологии барбуса Смита Puntioplites proctozystron (Bleeker, 1865) в дельте реки Меконг
No full textFisheries in the Mekong River are characterized by high pressure and extremely low selectivity towards fishing targets, which greatly complicates the conservation and possible restoration of the region's biodiversity. Relevance. Knowledge of fish population structure and biology is essential for fishery management and rational use of resources; however, the fisheries of the region are predominantly artisanal, for which the information on catches is scarce. This work is aimed at a study of the morphological characteristics of Smith's barb Puntioplites proctozystron (Bleeker, 1865) and the distribution of its quantitative parameters. The data have been collected from the bottom trawl catches in the Mekong River Delta that were conducted using a beam trawl in the low water and flood periods of 2018–2022. The average abundance and biomass of this species in fresh waters were 8.3±20.8 ind./ha and 114.7±229.4 g/ha, and in the estuary they were 0.6±2.7 ind./ha and 12.1±63.5 g/ha. These quantitative parameters for Smith's barb in the relatively shallow and low-flow Hau River and its estuarine channels were statistically significantly higher than in the rest of the delta estuary system (8.5±22.2 ind./ha and 110.7±248.7 g/ha as compared to 1.4±6.5 ind./ha and 25.0±90.1 g/ha). Examination of morphological characteristics showed a very low variability of traits in mature individuals; the coefficient of variation was less than 10 %. The obtained results indicate the absence of sexual dimorphism and different morphotypes in the population, provide the ground for minimum landing size recommendations, and can serve as a foundation for the further population research of this species.Рыболовство в реке Меконг отличается высокой нагрузкой и крайне малой избирательностью в отношении объектов промысла, что значительно осложняет сохранение и возможное восстановление биоразнообразия региона. Для управления промыслом и рационального использования ресурсов необходимы знания о популяционной структуре и биологии рыб, однако на реке в основном преобладает кустарное слабо учитываемое рыболовство. Целью работы стало исследование морфологических характеристик барбуса Смита Puntioplites proctozystron (Bleeker, 1865) и распределения его количественных показателей. Для исследований использованы уловы донных тралений в дельте р. Меконг, проводившихся бимтралом в меженные и паводковые периоды 2018–2022 гг. Результаты. Средняя численность и биомасса вида в пресных водах составляла 8,3±20,8 экз./га и 114,7±229,4 г/га, а в эстуарии — 0,6±2,7 экз./га и 12,1±63,5 г/га. Обилие барбуса Смита в более маловодной и мелководной реке Хау и ее устьевых протоках было статистически достоверно выше, чем в остальной части дельтово-эстуарной системы (8,5±22,2 экз./га и 110,7±248,7 г/га против 1,4±6,5 экз./га и 25,0±90,1 г/га). Исследования морфологических (пластических) показателей показали весьма низкую изменчивость признаков у половозрелых особей; коэффициент вариаций признаков был менее 10 %. Полученные данные свидетельствуют об отсутствии полового диморфизма и различных морфотипов в популяции, позволяют дать рекомендации по ограничению минимальных размеров при вылове и могут служить основой для дальнейших популяционных исследований вида.PublishedReferee
Mapping the seabed of the Colombian Caribbean: Proposal for a cartographic scheme of the underwater geomorphology of Colombia (South and Central Section of the continental margin)
No full textEsta publicación muestra los avances obtenidos en el proyecto de mapeado geomorfológico y estructural submarino del territorio marítimo colombiano, el cual parte desde el diseño de un esquema cartográfico para el Caribe que se dividió en 22 cartas a escala 1:250 000. En este trabajo se avanza con la presentación de dos primeras cartas desarrolladas entre los años 2020 y 2021. La elaboración de estas cartas se realizó con el uso de información batimétrica, sísmica 2D, anomalías magnéticas y gravimétricas, y datos satelitales, todo integrado bajo herramientas de sistemas de información geográficas (SIG). Como resultado se obtuvieron las unidades geomorfológicas que caracterizan la parte sur-central del margen continental del Caribe colombiano en dos cartas temáticas enumeradas 1408 y 1409, acorde a lo establecido en el esquema cartográfico diseñado para tal propósito.This paper shows the progress made in relation to the project to carry out submarine geomorphological and structural mapping of Colombian maritime territory, which started with the design of a cartographic grid divided into 22 charts at a scale of 1:250 000. This paper presents the first two charts developed between the years 2020-2021. These charts were prepared with the use of bathymetric information, 2D seismic data, magnetic and gravimetric anomalies, and satellite data, all integrated in Geographic Information Systems (GIS). As a result, the geomorphological units that characterize the southern and central part of the continental margin of the Colombian Caribbean were published in two thematic charts numbered 1408 and 1409, as established in the cartographic grid designed for this purpose.PublishedNot Know
Heavy metals risk assessment for consumption of wild Mediterranean mussels Mytilus galloprovincialis Lamarck, 1819 along Samsun Coasts of the Black Sea
No full textThe present study aimed to determine the concentration of metals in the soft tissue of wild mussels in coastal of Samsun and to assess human consumption. Using inductively coupled plasma mass spectrometry, the quantities of cadmium, mercury, lead, copper, iron, and zinc in Mytilus galloprovincialis were measured. The heavy metals found in Mediterranean mussels are arranged in the following ascending order: Cd < Hg < Pb < Cu < Fe < Zn. Concentrations of toxic metals were safe according to European Commission guidelines and the Ministry of Agriculture, Forestry and Fisheries. According to the estimated daily intake (EDI), eating Mediterranean mussels poses no risks. The target hazard quotients (THQs) in metals are also found <1, which implies no threat to consumers. In conclusion, the current study confirmed that the concentration of heavy metals in the Mediterranean mussels is safe for people intake in terms of their toxicity.PublishedReferee
Оценка гидрохимического состояния Азовского моря по данным натурных исследований 2021–2022 гг.
No full textThis paper presents the results of the investigation of the dynamics of the main hydrochemical characteristics of the Azov Sea in the autumn seasons of 2021–2022. Over this time range, a change in the oxygen regime of the Azov Sea has been recorded. The concentrations of ammonium, nitrate, and total nitrogen, as well as total phosphorus have a considerable impact on the level of primary production of organic matter by phytoplankton. At the present period of a low river flow, the concentration of biogenic elements is decreasing, which leads to a decrease in the primary production of organic matter.В работе представлены результаты исследования динамики основных гидрохимических характеристик Азовского моря в осенний период 2021–2022 гг. Отмечено изменение кислородного режима Азовского моря в исследуемый период. Концентрации аммонийного, нитратного, а также общего азота и фосфора в Азовском море оказывают существенное влияние на уровень первичного продуцирования органического вещества фитопланктоном. В современный период низкого уровня речного стока концентрация биогенных веществ уменьшается, что приводит к снижению первичного продуцирования органического вещества.PublishedNon Referee
Решение задачи оптимизации рыбодобывающей деятельности.
No full textA model for optimal planning of fishing activities has been proposed. It includes the formation of a biological component (a set of fishing objects considered taking into account their distribution over fishing zones) and a technological component (a set of fishing vessels and fishing technologies). On the basis of these two components, the technological chain "field object – production vessel – production technology" is formed. For each type of fishing vessel, it is permissible to use a certain type (or several types) of fishing technologies that are directly related to fishing objects, their catch can be carried out only using a certain production technology. Particular attention in the model is given to the problem of determining the optimal quantitative composition of the production fleet. The optimization criterion is the minimization of the costs associated with the fishing activities of specialized vessels, provided that the specified volumes of catch are achieved. The costs are directly related to the types of vessels used, fuel costs depending on the vessel's home port and the time required for loading and unloading operations. In the optimization problem, estimates of the weighted average daily catch and fishing time are used to account for most of the costs associated with the extraction of aquatic biological resources. The optimization algorithm is considered on the example of the Commander squid (Berryteuthis magister) in the North Kuril zone. In the area under consideration, squid production is carried out using trawl technology. The main types of vessels engaged in squid harvesting are large-capacity and medium-capacity vessels.Предлагается модель оптимального планирования рыбодобывающей деятельности, включающая в себя формирование биологического компонента (совокупности промысловых объектов, рассматриваемых с учетом их распределения по промысловым зонам) и технологического компонента (совокупность добывающих судов и технологий промысла). На основе этих компонент формируется технологическая цепочка "объект промысла – добывающее судно – технология добычи". Для каждого типа промыслового судна допустимо использование определенного вида (или нескольких видов) технологий промысла, напрямую связанных с промысловыми объектами, добыча которых осуществляется только с применением определенной технологии. Особое внимание в модели отводится задаче определения оптимального количественного состава добывающего флота. Критерием оптимизации является минимизация издержек, связанных с рыбодобывающей деятельностью специализированных судов при условии достижения заданных объемов добычи (вылова). Издержки напрямую связаны с используемыми типами судов, топливными расходами, которые зависят от порта базирования судна и времени, необходимого для осуществления погрузо-разгрузочных работ. В задаче оптимизации используются оценки средневзвешенного суточного вылова и промыслового времени для учета большинства издержек, связанных с процессом добычи водных биологических ресурсов. Алгоритм оптимизации рассмотрен на примере добычи кальмара командорского (Berryteuthis magister) в Северо-Курильской зоне, вылов которого ведется с использованием траловой технологии. Основными типами судов, осуществляющими добычу кальмара, являются крупнотоннажные и среднетоннажные суда.PublishedReferee
A rare stranding event of the short beaked common dolphin (Delphinus delphis) in the eastern Tunisian coastline
No full textA short beaked common dolphin was found stranded on March 3rd 2021, on Hammamet beach (Central-eastern Tunisia). This is a rare stranding event since it represents the third documented stranded individual reported on Tunisian coastline for half a century. Necropsy of the freshly dead female dolphin was conducted to know the presumable cause of death. The pregnant dolphin was bearing a mid-term female fetus with fully developed organs. Detailed biometric data were taken for both individuals. Samples were collected and preserved in the tissue bank of the national stranding network. The freshly dead fetus is preserved at the oceanographic museum for scientific collection. The rare stranding of this species observed here would be attributed to the small population frequenting Tunisian waters. This note improves knowledge on this poorly studied species in the south-central Mediterranean area.PublishedReferee